TAMPA (FOX 13) - A new report by the American Lung Association has many people holding their breath.

The annual “State of the Air” report released Wednesday reveals about 52 percent of the U.S. population lives in unhealthy air levels.

The report also reveals some shocking statistics for the air in the Bay area.

Hillsborough County, for instance, was ranked 73rd on the list of 197 cities with high ozone days.

The ranking resulted in an “F” score for the county’s air, and while it was the worst among others in the Bay area, Hillsborough’s neighboring counties didn’t fare much better.

Other counties were given the following scores:

Manatee ‘C’

Sarasota ‘D’

Pinellas ‘C’

Polk ‘D’

Pasco ‘B’

The report, which covers data collected between 2012 and 2014, measures year-round particle pollution, or the average amount of tiny solid and liquid particles found in the air over a year.

It also measures short-term particle pollution and ozone pollution- also known as smog- which is created when gases that come out of tailpipes, smokestacks and other sources come into contact with sunlight.

Breathing in air contaminated with any of these pollutants is associated with early death, cardiovascular harm, respiratory disease and cancer, yet the study found nearly 20 million people in the U.S. are living with unhealthy levels of all three.